La lagune Gbaga est constituée d'écosystèmes très fragiles et toutes les espèces qui s'y trouvent sont menacées et en voie de disparition. La méthodologie repose sur la collecte et le traitement de données hydrométriques et granulométriques, complétées par des mesures in situ et des analyses en laboratoire basées sur des échantillons des différentes espèces capturées au cours des différentes saisons hydrologiques.

This research aims to evaluate the feasibility of using multiple rainfall-runoff hydrologic models Génie Rural à 4, 5, 6 paramètres Journalier (GR4J, GR5J, and GR6J) in the Upper Benue River (UBR) in Northern Cameroon. By using the Michel's calibration algorithm, we found that the composite criterion is the most sustainable objective function for model optimization. An honest evaluation empirically proves that the GR6J model performs better than the other two models follow by GR5J.

The results showed that there is an variability in the spatial distribution of extreme indices with an upward and downward trend of dry and wet rainfall periods in West Africa in both historical and projected periods. Thus, the results revealed that the spatio- temporal variability of extreme rainfall can have repercussions on the hydrological functioning of watersheds, water availability and water-dependent activities.

The objective is to assess the causes of exceptional floods in the Ouémé basin using the HEC-RAS model. The results of the calculation made it possible to characterize: the losses and damage due to human settlement on the banks and agricultural production in the flood zone, the flooded extent and the height of submersion depend on the return period, most of the Flood waters converge towards the west of the basin (low risk) and towards the east around the Damè-Wogon depression (high risk).

The impact of climate change on precipitation and water availability is of major concern for policy makers in the Mono Basin of West Africa, whose economy mainly depends on rainfed agriculture and hydropower generation. The objective of this study is to project rainfall, flows and evapotranspiration (ET) in the future period and understand their changes across Mono River Basin.